Various methods and an apparatuses for determining the internal temperature of a living body or of an object have been developed. Typically, clinical thermometers are required for measuring the body temperature of a living being. Such thermometers are usually inserted, for example, in the mouth or ear of the patient so as to get as close a reading of the internal body as possible. Such thermometers are unpractical when frequent or continuous temperature measurements are required.
Other solutions have been developed such as thermometers measuring the temperature of a human being from the surface of the skin or of the body of an object from its surface. For example U.S. Pat. No. 5,816,706 discloses a method and apparatus comprising measuring thermal flux from the surface of an object through a structure which is positioned against it and whose thermal conductivity is known. The disclosed method and apparatus use a static thermal model of the thermal flux that provides for thermal resistivity but does not take into account thermal capacity, i.e. the capacity of storing thermal energy. This causes problems when the apparatus is subject to rapid or instantaneous change in ambient temperature as this will be reflected by an equally rapid or instantaneous change on estimated body temperature, and vice versa.
Thus, there is a need for a dynamic method and apparatus for measuring the temperature of a human being from the surface of the skin, or of the body of an object from its surface, so that it does not provide erroneous values when subjected to rapid or instantaneous temperature changes.